Avant-garde music and theatre of all the performing arts, none has been more circumspect about its theatrical nature than classical concert music. A romantic ideology that located musical content in sounds rather than actions or locations, and that accordingly identified composer rather than performer as the primary origin of that content, came to ensure that the act of performance was, as far as possible, rendered invisible. The theatre of musical performance was largely limited to a carefully circumscribed ritual of dress and behaviour; the performer who sought to assert his or her individuality over and above this ritual risked accusations of charlatanism. On the face of it, the postwar avant-garde in Europe and America, while enthusiastically dispensing with other aspects of musical tradition, represented the apotheosis of this downplaying of the business of performance. Here was a music that elevated the abstract sonic configuration to the status of a fetish, that finally eradicated the pleasure of the performer as a compositional consideration, and that seemed more at home in the lecture room or the computer lab than the concert hall. As Paul Griffiths has noted, ‘in the 1950s … few young composers wanted to work in the theatre. Indeed, to express that want was almost enough … to separate oneself from the avant-garde’ (1995, 171). And yet this apparently arid terrain for theatrical endeavour was soon touched by developments that, conversely, prepared the ground for quite new sorts of musical theatre. During the second half of the 1950s, the music of the avant-garde became, albeit frequently unwittingly, suffused with the spirit of theatre.